ScienceAges 13-15

Human body systems & organs

Connect major human organs and systems to digestion, circulation, respiration and coordination. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 13-15

Human body systems & organs

Take your time. Show your thinking.

1. In which long, folded organ of the digestive system are most digested nutrients absorbed into the bloodstream through tiny finger-like villi: the small intestine or the oesophagus?
Heart · Lungs · Digestive Tract
2. Where does digestion begin in the human body through chewing and the action of salivary amylase: in the mouth or in the large intestine?
Heart · Lungs · Digestive Tract
3. Which microscopic blood vessels have walls only one cell thick to allow rapid exchange of oxygen, nutrients and waste with body tissues: capillaries or arteries?
Heart · Lungs · Digestive Tract
4. Which dome-shaped muscle beneath the lungs contracts and flattens when you inhale, increasing chest volume and drawing air in: the diaphragm or the bicep?
Heart · Lungs · Digestive Tract
5. Why is dietary fibre (roughage from vegetables, fruits and whole grains) important even though humans cannot digest it: it keeps food moving smoothly through the intestines, or it turns into bone?
Heart · Lungs · Digestive Tract
6. Which nutrient group serves as the body’s primary fuel for cellular respiration (found in rice, bread, pasta and fruit): carbohydrates or minerals?
Heart · Lungs · Digestive Tract
7. What is the main function of the large intestine (colon): to absorb remaining water from undigested food waste, or to pump blood?
Heart · Lungs · Digestive Tract
8. What are the tiny air sacs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses out: alveoli or villi?
Heart · Lungs · Digestive Tract
9. Which muscular tube carries swallowed food from the mouth down to the stomach by wave-like contractions (peristalsis): the oesophagus (gullet) or the trachea (windpipe)?
Heart · Lungs · Digestive Tract
10. Which class of digestive enzymes breaks down proteins into amino acids: proteases or amylases?
Heart · Lungs · Digestive Tract
11. Which mineral is essential for building strong bones and teeth (found in dairy products, leafy greens and small fish): calcium or sodium?
Heart · Lungs · Digestive Tract
12. Which blood vessels carry blood BACK toward the heart and contain valves to prevent backflow: veins or arteries?
Heart · Lungs · Digestive Tract

12 questions · Seed 104737 · Age guidance, not curriculum certification

View the answer key

Worksheet StudioAnswer key · Ages 13-15

Human body systems & organs

Answers and reasoning. Review before teaching.

1. In which long, folded organ of the digestive system are most digested nutrients absorbed into the bloodstream through tiny finger-like villi: the small intestine or the oesophagus?
Small intestine
Villi and microvilli in the small intestine provide a huge surface area for nutrient absorption.
2. Where does digestion begin in the human body through chewing and the action of salivary amylase: in the mouth or in the large intestine?
In the mouth
Teeth mechanically break down food while saliva begins digesting starch into maltose.
3. Which microscopic blood vessels have walls only one cell thick to allow rapid exchange of oxygen, nutrients and waste with body tissues: capillaries or arteries?
Capillaries
Thin capillary walls provide a short diffusion pathway between blood and cells.
4. Which dome-shaped muscle beneath the lungs contracts and flattens when you inhale, increasing chest volume and drawing air in: the diaphragm or the bicep?
Diaphragm
Contraction of the diaphragm and intercostal muscles expands the thorax, lowering pressure so air flows into the lungs.
5. Why is dietary fibre (roughage from vegetables, fruits and whole grains) important even though humans cannot digest it: it keeps food moving smoothly through the intestines, or it turns into bone?
It keeps food moving smoothly through the intestines
Fibre adds bulk to aid peristalsis and prevent constipation.
6. Which nutrient group serves as the body’s primary fuel for cellular respiration (found in rice, bread, pasta and fruit): carbohydrates or minerals?
Carbohydrates
Carbohydrates are broken down into glucose, the main fuel for cellular respiration.
7. What is the main function of the large intestine (colon): to absorb remaining water from undigested food waste, or to pump blood?
To absorb remaining water from undigested food waste
The large intestine reabsorbs water and electrolytes, leaving semi-solid faeces.
8. What are the tiny air sacs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses out: alveoli or villi?
Alveoli
Millions of alveoli in the lungs provide a large moist surface area surrounded by capillaries for gas exchange.
9. Which muscular tube carries swallowed food from the mouth down to the stomach by wave-like contractions (peristalsis): the oesophagus (gullet) or the trachea (windpipe)?
Oesophagus (gullet)
Peristalsis in the oesophagus pushes the food bolus into the stomach.
10. Which class of digestive enzymes breaks down proteins into amino acids: proteases or amylases?
Proteases
Proteases (such as pepsin and trypsin) hydrolyse proteins into amino acids.
11. Which mineral is essential for building strong bones and teeth (found in dairy products, leafy greens and small fish): calcium or sodium?
Calcium
Calcium phosphate gives bones and tooth enamel their hardness and strength.
12. Which blood vessels carry blood BACK toward the heart and contain valves to prevent backflow: veins or arteries?
Veins
Veins operate at lower pressure and use one-way valves to keep blood flowing toward the heart.

12 questions · Seed 104737 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 13-15

Human body systems & organs

Take your time. Show your thinking.

1. In which long, folded organ of the digestive system are most digested nutrients absorbed into the bloodstream through tiny finger-like villi: the small intestine or the oesophagus?
Heart · Lungs · Digestive Tract
2. Where does digestion begin in the human body through chewing and the action of salivary amylase: in the mouth or in the large intestine?
Heart · Lungs · Digestive Tract
3. Which microscopic blood vessels have walls only one cell thick to allow rapid exchange of oxygen, nutrients and waste with body tissues: capillaries or arteries?
Heart · Lungs · Digestive Tract
4. Which dome-shaped muscle beneath the lungs contracts and flattens when you inhale, increasing chest volume and drawing air in: the diaphragm or the bicep?
Heart · Lungs · Digestive Tract
5. Why is dietary fibre (roughage from vegetables, fruits and whole grains) important even though humans cannot digest it: it keeps food moving smoothly through the intestines, or it turns into bone?
Heart · Lungs · Digestive Tract
6. Which nutrient group serves as the body’s primary fuel for cellular respiration (found in rice, bread, pasta and fruit): carbohydrates or minerals?
Heart · Lungs · Digestive Tract
7. What is the main function of the large intestine (colon): to absorb remaining water from undigested food waste, or to pump blood?
Heart · Lungs · Digestive Tract
8. What are the tiny air sacs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses out: alveoli or villi?
Heart · Lungs · Digestive Tract
9. Which muscular tube carries swallowed food from the mouth down to the stomach by wave-like contractions (peristalsis): the oesophagus (gullet) or the trachea (windpipe)?
Heart · Lungs · Digestive Tract
10. Which class of digestive enzymes breaks down proteins into amino acids: proteases or amylases?
Heart · Lungs · Digestive Tract
11. Which mineral is essential for building strong bones and teeth (found in dairy products, leafy greens and small fish): calcium or sodium?
Heart · Lungs · Digestive Tract
12. Which blood vessels carry blood BACK toward the heart and contain valves to prevent backflow: veins or arteries?
Heart · Lungs · Digestive Tract

12 questions · Seed 104737 · Age guidance, not curriculum certification

Worksheet StudioAnswer key · Ages 13-15

Human body systems & organs

Answers and reasoning. Review before teaching.

1. In which long, folded organ of the digestive system are most digested nutrients absorbed into the bloodstream through tiny finger-like villi: the small intestine or the oesophagus?
Small intestine
Villi and microvilli in the small intestine provide a huge surface area for nutrient absorption.
2. Where does digestion begin in the human body through chewing and the action of salivary amylase: in the mouth or in the large intestine?
In the mouth
Teeth mechanically break down food while saliva begins digesting starch into maltose.
3. Which microscopic blood vessels have walls only one cell thick to allow rapid exchange of oxygen, nutrients and waste with body tissues: capillaries or arteries?
Capillaries
Thin capillary walls provide a short diffusion pathway between blood and cells.
4. Which dome-shaped muscle beneath the lungs contracts and flattens when you inhale, increasing chest volume and drawing air in: the diaphragm or the bicep?
Diaphragm
Contraction of the diaphragm and intercostal muscles expands the thorax, lowering pressure so air flows into the lungs.
5. Why is dietary fibre (roughage from vegetables, fruits and whole grains) important even though humans cannot digest it: it keeps food moving smoothly through the intestines, or it turns into bone?
It keeps food moving smoothly through the intestines
Fibre adds bulk to aid peristalsis and prevent constipation.
6. Which nutrient group serves as the body’s primary fuel for cellular respiration (found in rice, bread, pasta and fruit): carbohydrates or minerals?
Carbohydrates
Carbohydrates are broken down into glucose, the main fuel for cellular respiration.
7. What is the main function of the large intestine (colon): to absorb remaining water from undigested food waste, or to pump blood?
To absorb remaining water from undigested food waste
The large intestine reabsorbs water and electrolytes, leaving semi-solid faeces.
8. What are the tiny air sacs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses out: alveoli or villi?
Alveoli
Millions of alveoli in the lungs provide a large moist surface area surrounded by capillaries for gas exchange.
9. Which muscular tube carries swallowed food from the mouth down to the stomach by wave-like contractions (peristalsis): the oesophagus (gullet) or the trachea (windpipe)?
Oesophagus (gullet)
Peristalsis in the oesophagus pushes the food bolus into the stomach.
10. Which class of digestive enzymes breaks down proteins into amino acids: proteases or amylases?
Proteases
Proteases (such as pepsin and trypsin) hydrolyse proteins into amino acids.
11. Which mineral is essential for building strong bones and teeth (found in dairy products, leafy greens and small fish): calcium or sodium?
Calcium
Calcium phosphate gives bones and tooth enamel their hardness and strength.
12. Which blood vessels carry blood BACK toward the heart and contain valves to prevent backflow: veins or arteries?
Veins
Veins operate at lower pressure and use one-way valves to keep blood flowing toward the heart.

12 questions · Seed 104737 · Age guidance, not curriculum certification